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Date: Wed, 1 Feb 2006 18:20:33 -0800 From: Eric Wing Subject: SDL/Universal Binary updates Hi Sam, Attached is a big set of changes to the Xcode projects to support Universal Binaries. I have also included .dmgs that include the prebuilt frameworks. Ryan, I also updated SMPEG which is also in the package. The SDL and smpeg binaries were built against the CVS version (pulled maybe a month ago?). I do not have an Intel Mac to test on so I have no idea if this stuff actually works. However, Christian Walther has been a big help in testing 10.2.8 and 10.3.9 so I'm fairly confident we got the build settings correct for at least PPC. I have attempted to document the important things for producing these Universal Binaries. Documentation is somewhat scattered through out everything, but there is a big centralized piece of documentation in the UniversalBinaryNotes.rtf in the SDL.dmg. As far as Universal Binaries are concerned, the big things were: - Build with gcc 3.3 on PPC, 4.0 on Intel. - We couldn't get any of the MMX/SSE code to compile/link (SDL and smpeg). - All 3rd party dependencies had to be rebuilt as Universal There were also a bunch of non-Universal things that have been updated: - I converted the SDL-satellites to create .dmg's instead of .pkg installers - Updated all 3rd party static libraries with current versions. (I think libpng was the most dramatic going from 1.0.? to 1.2.8 with API breakage. I haven't found any problems so far in doing this.) - Changed some compiler optimization settings - Finally updated the exports list for SDL_mixer - Tried to include a static smpeg in SDL_mixer (multiple build variants in Xcode project now) - Enabled Altivec in SDL (we forgot to add the flags to Xcode last time) - More documentation Since so many things have changed, there might be new problems introduced. The big issue I've found so far is with SDL_mixer. As I mentioned on the mailing list, MP3's produce an assertion failure. And the MikMod problem reported on Bugzilla continues to persist. There's probably a bunch of other stuff I'm forgetting. There really were hundreds of little things I mucked with so it's hard to remember them all. If you have any questions, feel free to ask. Thanks, Eric
author Sam Lantinga <slouken@libsdl.org>
date Thu, 02 Feb 2006 06:26:39 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>Audio</TITLE
><META
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><DIV
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><H1
><A
NAME="AUDIO"
></A
>Chapter 10. Audio</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="sdlaudiospec.html"
>SDL_AudioSpec</A
>&nbsp;--&nbsp;Audio Specification Structure</DT
><DT
><A
HREF="sdlopenaudio.html"
>SDL_OpenAudio</A
>&nbsp;--&nbsp;Opens the audio device with the desired parameters.</DT
><DT
><A
HREF="sdlpauseaudio.html"
>SDL_PauseAudio</A
>&nbsp;--&nbsp;Pauses and unpauses the audio callback processing</DT
><DT
><A
HREF="sdlgetaudiostatus.html"
>SDL_GetAudioStatus</A
>&nbsp;--&nbsp;Get the current audio state</DT
><DT
><A
HREF="sdlloadwav.html"
>SDL_LoadWAV</A
>&nbsp;--&nbsp;Load a WAVE file</DT
><DT
><A
HREF="sdlfreewav.html"
>SDL_FreeWAV</A
>&nbsp;--&nbsp;Frees previously opened WAV data</DT
><DT
><A
HREF="sdlaudiocvt.html"
>SDL_AudioCVT</A
>&nbsp;--&nbsp;Audio Conversion Structure</DT
><DT
><A
HREF="sdlbuildaudiocvt.html"
>SDL_BuildAudioCVT</A
>&nbsp;--&nbsp;Initializes a SDL_AudioCVT structure for conversion</DT
><DT
><A
HREF="sdlconvertaudio.html"
>SDL_ConvertAudio</A
>&nbsp;--&nbsp;Convert audio data to a desired audio format.</DT
><DT
><A
HREF="sdlmixaudio.html"
>SDL_MixAudio</A
>&nbsp;--&nbsp;Mix audio data</DT
><DT
><A
HREF="sdllockaudio.html"
>SDL_LockAudio</A
>&nbsp;--&nbsp;Lock out the callback function</DT
><DT
><A
HREF="sdlunlockaudio.html"
>SDL_UnlockAudio</A
>&nbsp;--&nbsp;Unlock the callback function</DT
><DT
><A
HREF="sdlcloseaudio.html"
>SDL_CloseAudio</A
>&nbsp;--&nbsp;Shuts down audio processing and closes the audio device.</DT
></DL
></DIV
><P
>Sound on the computer is translated from waves that you hear into a series of 
values, or samples, each representing the amplitude of the wave.  When these
samples are sent in a stream to a sound card, an approximation of the original
wave can be recreated.  The more bits used to represent the amplitude, and the
greater frequency these samples are gathered, the closer the approximated
sound is to the original, and the better the quality of sound.</P
><P
>This library supports both 8 and 16 bit signed and unsigned sound samples,
at frequencies ranging from 11025 Hz to 44100 Hz, depending on the 
underlying hardware.  If the hardware doesn't support the desired audio
format or frequency, it can be emulated if desired (See 
<A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio()</TT
></A
>)</P
><P
>A commonly supported audio format is 16 bits per sample at 22050 Hz.</P
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